在城市燃气的可燃成分中，最具有剧毒性而含量较多者为（）。故把含有该组分的燃气视为“有 发布时间：2018-01-28 02:21 │ 来源：www.tikuol.com 题型：单项选择题 问题： 在城市燃气的可燃成分中，最具有剧毒性而含量较多者为（）。故把含有该组分的燃气视为“有毒燃气”，而规定了对有毒而又无臭味的燃气应加臭A、CO2B、C2H6C、NOD、CO
题型：单项选择题 综合填空。parent, tell, call, celebrate, together, why, start, after, shop, newspaper Most people buy lots of presents just before Christmas. But some people think we buy too much. Theystart a special day 1. Buy Nothing Day. They don't want anyone to go 2. on that day. Buy Nothing Day is on November 29. It is 3. Thanksgiving. Often, before Christmas we see many ads.in 4. and on TV 5. us to "buy, buy, buy!" The idea for Buy Nothing Day 6. in Vancouver, Canada. Now people all over the world 7. Buy Nothing Day. In California, the U.S., 8. and children get 9. to read stories, sing songs and draw pictures. The children talk about 10. they can't get many toys. 查看答案