分詞是由動詞變化而來，可分為現在分詞(Ving)與過去分詞(Ven)。分詞可具有形容詞功用，以修飾名詞或作補語；分詞亦可作副詞，以修飾動詞或整個子句。
1. 分詞當形容詞，以修飾名詞或當補語，可分為下列幾種情況：
(a)Ving + N
Ven + N
這種結構分詞是修飾後面的名詞，表達主動或進行用現在分詞，表達被動或完成用過去分詞。
例：1. He told us some frightening stories. (令人害怕的，表示主動)。
2. The wounded soldier was taken off to hospital. (受傷的，表示被動)。
3. A rolling stone gathers no moss. (滾石不生苔) (滾動的，表示進行)。
4. He threw away the broken chair. (破的，表示完成)。
上列結構要判斷主動被動，進行完成，通常要拉後面名詞與分詞的關係。
上列各句的分詞結構可作適度轉換:
frightening stories = stories which are frightening
the wounded soldier = the soldier who was wounded
a rolling stone = a stone which is rolling
the broken chair = the chair which has broken.
(b)N + Ving
N + Ven
這種結構分詞置於名詞的後面，通常是由形容詞子句簡化而成的分詞片語。主動語態用現在分詞(Ving)，被動語態用過去分詞(Ven)。
例：1. The girl wearing a hat is Mary. (a hat為名詞片語，故前面分詞應為主動語態)
= The girl who is wearing a hat is Mary.
2. It is a famous book written by Henry James. (by得知為被動)
= It is a famous book which was written by Henry James.
3. The bridge built in 1910 was torn down. (拉build與bridge之關係，得知為被動)
= The bridge which was built in 1910 was torn down.
再度提醒您，上列分詞結構一定要懂得判斷主動被動。
(c) be
S+ feel + Ving / Ven
become
這種結構的分詞是由情緒動詞變化而來的，
若用事物作主詞，表達“令人‥”則為主動觀念，用現在分詞(Ving)；
若用人作主詞，表達“感到‥”則為被動觀念，用過去分詞(Ven)。
例：1. We are surprised at the result.
2. After a long day’s work, John felt exhausted. (精疲力盡的)
3. The movie was exciting.
4. His stories are always interesting.
註：這類情緒動詞尚包括tire(疲倦), confuse(困惑), puzzle(困惑), fascinate(吸引), disappoint(失望), touch(感動), move(感動), embarrass(困窘), frighten(驚嚇)等。
2. 分詞當副詞，以修飾動詞或整個子句，主動語態用現在分詞，被動語態則用過去分詞。
(a) Ving, S + VP
Ven, S + VP
此種結構分詞是修飾後面整個子句。
例：1. Writing a letter, he heard somebody coming. (關鍵在a letter為名詞片語，故為主動觀念，用現在分詞)
2. Frightened by the explosion(爆炸聲)，the children began to cry. (關鍵在by，故用過去分詞)
3. Walking on the street, I met John. (本句walking後面沒有名詞片語，也沒有by，故拉主詞I與walk之關係，得知應為主動觀念，故用現在分詞)
4. Written in simple English, the book soon became popular. (拉book與write之關係)。
(b) S+ V+ Ving
S+ V+Ven
此種結構分詞用來修飾動詞，判斷的關鍵亦在主動被動的觀念。
例：1. The woman came here wearing a red hat.
2. My friend entered the room singing and laughing.
