1. (如果参加)eco-travel and you will find it will help you understand the importance of nature.(take)
2. He was so angry with himself for ______________________(犯了个如此愚蠢的错误). (so).
3. Luckily, we brought a road map with us without which _____________________(我们就迷路了).(get)
4. _____________________ (人们所忧虑的事)is weather the poisoned milk powder attracting public attention will be on the market continually. (concern)