—It is _______he often fails in exams_______ makes his parents worried about him.—So, he has to work whole-heartedly.
Thank you very much for the trouble you have taken _________ me with my English.
Before the conference, a new problem came up __________ could speak on behalf of our group.
He dressed up and went to the party as if ___________.
Scientist are not sure about the ___________ of water on the Mars.
Don’t push me! __________ you know the truth right away?