pass by可以直接结尾，后面可以不加宾语，但是pass需要加宾语或者介词
【例句】
pass by
They were injured when a parked car exploded as their convoy passed by.
他们的车队经过时，一辆停放着的汽车爆炸了，他们受了伤。
As they pass by, a piteous wailing is heard.
他们经过时，响起了令人哀怜的恸哭。
pass
As she passed the library door, the telephone began to ring
她经过图书室门口时，电话响了。
He passed through the doorway into Ward B
他穿过门口进入B病房。
pass 英[pɑ:s] 美[pæs]
vt. 通过; 走过; 批准; 度过;
vt. 传球; 及格; 发生; 不要;
n. 通行证; 通道; 关口; 越过;
[例句]As she passed the library door, the telephone began to ring
她经过图书室门口时，电话响了。
pass by 英[pɑ:s bai] 美[pæs baɪ]
[词典] 经过; 过去; 疏忽; 以…为人所知;
[例句]I see them pass by my house every day
我每天看见他们从我家旁边经过。