The fact has worried many scientists _______the earth isbecoming warmer and warmer these years. []

____ it snowed heavily yesterday, nobodyin our class missed the lesson．

Your father is very strict with you.—- ____. He never lets off a single mistake of ours.

Heroes ______ their life ______ becoming the best they can be, whether it is President of the United States, a mother, or a firefighter.

下列加点词语的活用与例句中加点词的活用类型相同的一项是例：江东虽小，地方千里，众数十万人，亦足王也。