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Question 1: Choose the correct tense for each sentence given below.

1. 'For seven days' is a signal word for Simple Present.
a. Present Perfect Progressive
b. Present Simple

2. 'Since 6 o'clock' is a signal word for Present Perfect Progressive.
c. Present Perfect Progressive
d. Present Simple

3. 'often' is a signal word for Present Perfect Progressive.
a. Present Perfect Progressive
b. Present Simple