Meaning of tì:
替
to substitute for; to take the place of; to replace; to stand in for
Wǒ jīntiān huì tì tā gōngzuò.
我今天会替她工作。
I will substitute for her at work today.
Tā ràng wǒ qù tì tā cānjiā huìyì.
他让我去替他参加会议。
He asked me to take his place at the meeting.
Wǒ kěyǐ tì nǐ wánchéng zhège rènwu.
我可以替你完成这个任务。
I can replace you to complete this task.
Tā yào tì wǒ qù cānjiā huìyì.
他要替我去参加会议。
He will attend the meeting in my place.
for; on behalf of
Wǒ kěyǐ tì nǐ wánchéng zhè xiàng rénwù.
我可以替你完成这项任务。
I can complete this task for you.
Wǒ kěyǐ tì nǐ wánchéng zhège rènwù.
我可以替你完成这个任务。
I can complete this task on your behalf.