Final answer:
The present continuous tense is used to fill in the blanks, resulting in 'I am reading' for the first sentence and 'Arun and Varun are watching' for the second, indicating actions taking place at the moment of speaking.
Step-by-step explanation:
Fill in the blanks with the present or past continuous tense:
- Don't disturb me. I am reading a book (read)
- Arun and Varun are watching a cartoon now (watch)
When constructing sentences in the present continuous tense, the structure usually follows the subject plus the verb to be (am/is/are) followed by the -ing form of the main verb. For instance, 'I am reading' and 'They are watching' illustrate this tense by indicating ongoing actions happening right now.
It's important to use the correct form of the verb 'to be' appropriate to the subject in question to properly convey the continuous aspect of the action. Remember, the present continuous tense is used for actions that are happening at the moment of speaking.