— You haven’t said a word about my new coua, Brenda. Do you like it ?— I’m sorry, I _____ anything about it sooner. I certainly think it’s pretty on you. 

They use computers to keep the traffic _______ smoothly. 

The experiment show that proper amount of exercise, if ________ regularly, can improve our health.

.I dislike__________when I am left alone to start a conversation with a stranger.

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