✔ 最佳答案
She did not know what to do, so she began to cry.(有因果關係)
She did not know what to do, and began to cry.(只是先後關係,未強調因果)
口語常用simple sentence或compound sentence,而不用complex sentence,可以依上面之一來說。
Didn't know what to do, she began to cry.這樣是不符英語語法的。因為前一句沒有主詞,前一句和後一句沒有連接詞,結果讀者分不出那裡是焦點,也看不出因果邏輯關係。
通常寫作才會用到complex sentence或分詞構句,因為較文雅。主要子句是句子的焦點,因此用這種寫法時,條理和因果邏輯關係較分明。