Production at the factory was________for two hours because there was no electricity.[ ]

Tom wants to be a singer and he_____ singing lessonsto do it.

Next week，my family are going to Austria and stay there for half a month.—________.

To tell you the truth, I have a hard time remembering all the ______ rules of English grammar.

Small sailboats can easily turn over in the water ______ they are not managed carefully.