提出建议的句型 — 英语填空题
题目
你的学校开展"绿色校园"活动。作为环保小卫士，你想向校长提出三条建议。请根据句意及首字母提示完成短文填空（每空一词）。Dear headmaster, To make our school greener, I think we s____ start a recycling project. It is a good idea t____ collect used bottles every Friday. Besides, why n____ ask students to use both sides of the paper?