The island, _____to the mainland by a bridge, is easy to go to [ ]

Do you enjoy the moves of Gangnam Style— ______ . I just do it to keep fit.

____today, he would get there by Friday.

The people in this country went through a period in their life________they had no freedom to use the cellphone.[ ]

(2013·高考安徽卷)It ________ be the vocabulary that caused you the problem in the exercise because you know a lot of words.