**Rule**: **Stative Verbs**. 'Comprise' (meaning 'to be made up of') is a stative verb. The **Simple Present Tense** is used to state a fact about composition. **Correct Usage**: 'comprises' correctly states a fact about the committee's structure. The subject 'The committee' is singular. **Incorrect Options**: (b) 'is comprising' is grammatically incorrect. (c) 'has comprised' is the wrong tense. (d) 'comprise' is a plural verb.

**Rule**: The **Present Perfect Continuous Tense** is used to emphasize the duration ('all afternoon') of a continuous action that started in the past and is still in progress. **Correct Usage**: 'has been sitting' perfectly describes the long, uninterrupted state of sitting. **Incorrect Options**: (a) 'sits' (Simple Present) is a habit. (b) 'is sitting' (Present Continuous) refers to the present moment only. (d) 'has sat' (Present Perfect) is less common for describing an ongoing state of sitting.

**Rule**: The **Simple Present Tense** is used to state a fact or introduce evidence. 'Evidence' is an uncountable noun and therefore takes a singular verb. **Correct Usage**: 'suggests' is the correct singular verb to state the conclusion drawn from the evidence. **Incorrect Options**: (b) 'is suggesting' is less common for stating a factual implication. (c) 'have suggested' is a plural verb. (d) 'suggest' is a plural verb.

**Rule**: The **Present Perfect Tense** can be used to report recent news or a recent accomplishment. The exact time is not important; the focus is on the achievement itself. **Correct Usage**: 'has passed' correctly reports the news of his success. While Simple Past ('passed') is also very common here, Present Perfect is used to emphasize the recentness and the current relevance of the news. **Incorrect Options**: (a) 'passes' (Simple Present) is a habit. (b) 'is passing' (Present Continuous) is for an action in progress. (d) 'pass' is a plural verb.

**Rule**: The **Present Continuous Tense** is frequently used to talk about fixed plans and arrangements in the near future. **Correct Usage**: The President's visit is a planned future event. 'is visiting' is the appropriate form to describe this arrangement. The Simple Present ('visits') could also be used if it's seen as a formal schedule, but Present Continuous is more common for personal or official arrangements. **Incorrect Options**: (c) 'has visited' (Present Perfect) is for past events. (d) 'visit' is the base form.

**Rule**: **Stative Verbs**. Verbs expressing mental states, emotions, or desires like 'hope', 'want', 'believe' are typically stative and are used in the **Simple Present Tense**, not the continuous form. **Correct Usage**: 'I hope' expresses the speaker's current feeling or wish. **Incorrect Options**: (a) 'am hoping' is sometimes used informally but is technically incorrect as 'hope' is a stative verb. (c) 'have hoped' is the wrong tense. (d) 'hopes' is for a third-person singular subject.

**Rule**: The **Present Perfect Continuous Tense** is used for an action that started at a point in the past ('since we arrived') and has continued repeatedly or without stopping until the present. **Correct Usage**: 'has been coughing' emphasizes the continuous and worrying nature of the coughing since a specific starting point. **Incorrect Options**: (a) 'coughs' (Simple Present) is a habit. (b) 'is coughing' (Present Continuous) is for now. (d) 'has coughed' (Present Perfect) focuses on single, completed coughs.

**Rule**: The **Simple Present Tense** is used to state economic principles, scientific laws, and general truths. **Correct Usage**: This sentence describes a fundamental economic principle that is always true. The subject 'The law' is singular, so the verb is 'determines'. **Incorrect Options**: (a) 'determine' is a plural verb. (c) 'is determining' (Present Continuous) implies a temporary action. (d) 'has determined' (Present Perfect) is the wrong tense for a permanent principle.

**Rule**: The **Present Perfect Continuous Tense** is used to talk about an action that has been in progress for a certain duration ('for only a few months') and has a present result ('she is already quite fluent'). **Correct Usage**: 'has been learning' emphasizes the continuous process of learning that has led to her current ability. **Incorrect Options**: (a) 'learns' (Simple Present) is a habit. (b) 'is learning' (Present Continuous) focuses on the present moment. (d) 'learned' (Simple Past) is a completed action.

**Rule**: The **Present Perfect Continuous Tense** is used for an action that started in the past and is still continuing, with an emphasis on the duration. **Correct Usage**: The phrase 'for the last two minutes' specifies the duration of the continuous action of ringing. 'has been ringing' perfectly captures this ongoing action over a period. **Incorrect Options**: (a) 'rings' (Simple Present) is a habit. (b) 'is ringing' (Present Continuous) is correct but doesn't incorporate the duration as well as the present perfect continuous. (d) 'rang' (Simple Past) is incorrect as the ringing is still happening.