Fighting an artificial greenhouse effect seems to be the greatest of environmental challenges, ________？

Living in the country，Peter doesn’t write often，but we do hear from him________.

look so upset, Jane． _____– I have been told my father has got skin cancer．

One of the sides of the board should be painted yellow，and________.

－Oh, it’s you, Steve! I ______ you. 　 －No surprising. I’ve just had my hair cut.