_____ have you been swimming? For five years.

You’re dropped __________ “s” in the word “across”.－Oh, you are right, __________ letter “s” should be doubled like this “cross”.

We feel our duty to make our country a better place.

What’s up?— The music in the restaurant sounds so________ that I want to leave at once.

Not until he questioned the manager several times ___________ that the engineer-in-chief had gone to an important meeting.