Explanation: In English grammar, subject-verb agreement is a fundamental principle that ensures the subject and verb in a sentence agree in number and person. This agreement is particularly important in the context of the present continuous tense, which is used to describe actions that are happening at the moment of speaking or around the present time.
The present continuous tense is formed using the auxiliary verb "to be" (am, is, are) followed by the main verb in its -ing form. For the first person singular pronoun "I," the correct form of the auxiliary verb "to be" is "am." Therefore, the sentence "I am watching TV now" is grammatically correct.
Let's break down the sentence:
- "I" is the subject and is in the first person singular.
- "am" is the auxiliary verb "to be" in the first person singular.
- "watching" is the main verb in its -ing form.
- "TV" is the object of the verb.
- "now" indicates the present time.
The other options are incorrect because:
- "Is" is used for the third person singular (he, she, it), not for the first person singular (I).
- "Are" is used for the second person (you) and the first and third person plural (we, they), not for the first person singular (I).
- "None of the above" is incorrect because "am" is the correct form for the first person singular in the present continuous tense.
Understanding subject-verb agreement and the correct use of the present continuous tense is essential for constructing grammatically correct sentences in English. This knowledge is particularly useful in competitive examinations where language proficiency is tested, such as UPSC, SSC, Bank PO, and CLAT.