look on indifferently; look on with folded arms; sit out; stand by

1. 他對需要做的各項工作并沒有袖手旁觀，而是精神抖擻地投入了工作。
   He did not stand about looking at all the job to be done; he waded straight in.
2. 只有一個人幫我們，其他人只是一聲不響地袖手旁觀。
   Only one man tried to help us, the rest just looked on in silence.
3. 在這種情況下，我們不會袖手旁觀。
   In that case we will not look on with folded arms.

袖的英語翻譯：

手的英語翻譯：

旁觀的英語翻譯：