In 1900, the energy derived from burning petroleum was only four percent ______ of coal.

Decision on whether the message is right or wrong should at least come after _____what the message is.

下面所述小儿的总热量中哪项所需热量是小儿最特殊的（）

小儿体格发育最快的时期是（）

It ‘s_____my power to make final decision on the matter.

The meeting _____ next week will be of great importance.

Mrs. Smith locked both the front and the back doors before she went to bed______thatsomeone might steal into the house at night.

Thanks to the militant feminist movement of the suffragettes before the First World War, votes were granted to women over the age of ________ in 1918.

Not all birds can fly , ______ do all birds build nests.

He would have given you more help, if he ________ so busy.