quicksand

1. N-UNCOUNT Quicksand is deep, wet sand that you sink into if you try to walk on it. 流沙[also N in pl]

The sandbank was uncertain, like quicksand under his feet. 這個沙丘不結實，像他腳下的流沙一樣。

2. N-UNCOUNT You can refer to a situation as quicksand when you want to suggest that it is dangerous or difficult to escape from, or does not provide a strong basis for what you are doing. 危機情形; 難以逃脫的情形; 無法爲所做之事提供基本保障的情形[also N in pl]

The research seemed founded on quicksand. 該研究倣彿建立在一磐散沙基礎上的。