**Rule**: **Stative Verbs**. 'Consist' is a stative verb describing composition and is not used in continuous tenses. The **Simple Present Tense** is used for scientific facts. **Correct Usage**: 'consists' correctly states the chemical makeup of water. The subject 'Water' is singular. **Incorrect Options**: (b) 'is consisting' is grammatically incorrect. (c) 'has consisted' is the wrong tense. (d) 'consist' is a plural verb.

**Rule**: **Stative Verbs**. 'Depend' is a stative verb expressing a state of reliance or connection. It is not used in continuous tenses. **Correct Usage**: 'depends' is the correct form to state this general truth about the speaker's opinion. The subject 'My opinion' is singular. **Incorrect Options**: (b) 'is depending' is grammatically incorrect. (c) 'has depended' is the wrong tense for a general truth. (d) 'depend' is a plural verb.

**Rule**: The **Present Perfect Tense** with 'just' is used to announce a very recent event that has important present consequences. **Correct Usage**: 'have just made' perfectly captures the breaking news of the discovery and its immediate impact. The subject 'The archaeologists' is plural. **Incorrect Options**: (a) 'make' (Simple Present) is a habit. (b) 'are making' (Present Continuous) is for an ongoing process. (d) 'makes' is a singular verb.

**Rule**: The **Present Perfect Continuous Tense** is used to explain a present result ('My hands are covered in paint') by describing the recent, continuous activity that caused it. **Correct Usage**: 'have been painting' emphasizes the activity that has just stopped or is still ongoing, which explains the current state of the speaker's hands. **Incorrect Options**: (a) 'paint' (Simple Present) is a habit. (c) 'painted' (Simple Past) disconnects the action from the immediate present result. (d) 'am painting' (Present Continuous) implies the action is still in progress, which is also possible, but the present perfect continuous gives a better sense of cause and effect.

**Rule**: The **Present Perfect Continuous Tense** is the best choice to describe an uninterrupted trend that has been happening over a long period ('for decades') and is still continuing. **Correct Usage**: 'has been rising' emphasizes the continuous, gradual increase over a long time. **Incorrect Options**: (a) 'rises' (Simple Present) is a general fact. (b) 'is rising' (Present Continuous) is for the current trend. (d) 'has risen' (Present Perfect) focuses on the total increase so far.

**Rule**: The **Present Continuous Tense** is used for an action happening right now. The command 'Hurry up!' indicates urgency and a currently occurring event. **Correct Usage**: 'is waiting' describes the ongoing action. The subject 'Everybody' is grammatically singular and takes a singular verb. **Incorrect Options**: (a) 'waits' (Simple Present) would be a habit. (b) 'wait' is a plural verb. (d) 'has waited' (Present Perfect) is the wrong tense for an action in progress.

**Rule**: The **Present Perfect Tense** is used to talk about a past change that has a visible result in the present. **Correct Usage**: 'have lost' indicates the process of losing weight is complete (or has reached a noticeable point), and the result is the person's current appearance. **Incorrect Options**: (a) 'lose' (Simple Present) is a habit. (b) 'are losing' (Present Continuous) refers to the process right now. (d) 'have been losing' emphasizes the process over time, which is also possible, but 'have lost' focuses more on the finished result being complimented.

**Rule**: The **Present Perfect Tense** is used to describe an action that was completed in the recent past and has a direct connection to the present. The focus is on the completion of the search in all places. **Correct Usage**: 'have looked' emphasizes that the action of searching everywhere is now complete, but the glasses are still not found. 'have been looking' would also be possible, emphasizing the duration of the search. **Incorrect Options**: (a) 'look' (Simple Present) is a habit. (b) 'am looking' (Present Continuous) means the search is in progress now. (c) 'have been looking' is also correct but focuses more on the ongoing activity rather than the completion of searching *everywhere*.

**Rule**: The **Present Perfect Tense** is used to describe an action that started in the past and has continued over a long duration ('for many years') up to the present. **Correct Usage**: 'has provided' correctly describes the company's long-standing policy that is still in effect. 'Company' is a singular subject. **Incorrect Options**: (a) 'provides' (Simple Present) states the policy as a fact without the historical context. (b) 'is providing' (Present Continuous) is for now. (d) 'provide' is a plural verb.

**Rule**: The **Present Continuous Tense** is used for actions in progress at the moment of speaking. The phrase 'I can't talk right now' indicates an ongoing action. **Correct Usage**: 'am having' correctly describes the action happening now. In this context, 'have' is a dynamic verb (meaning 'to take'). **Incorrect Options**: (a) 'have' (Simple Present) would imply possession or a habit, which doesn't fit. (c) 'have had' (Present Perfect) refers to a completed past action. (d) 'has' is for third-person singular subjects.