Most birds find it safe to sleep in the trees, but __________ they have eggs or young chicks, they don’t use a nest.
—Do you have anything more ___, sir? —Not at the moment. Have a rest then.
Which do you enjoy ___ your spare time, reading or playing chess?
The way she thought of _____ enough money was to sell her hair.
Well, who would you rather ____ with you to the theatre, George or me?
Wang Hua is said ____a new computer program recently, but I don’t know when she will finish it.