How much is _______ for a schoolbag? —Experts say students should carry_______ more than 10 or 15 percent of their body weight.

He was expecting to have completed the job by now ., he’s only halfway through it .

She may have missed the train,____ she won’t arrive for another hour.

下列各句中，表达得体的一句是

Mom, shall we have supper now—Oh, we won’t have supper _______ your dad comes back.