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urdu speak about go for it,don't give up....

come on, go for it,
i dont know exact words for it, but when someone encourages us, it is their tone which reflects the mood and encouragement one way could be chalo, chalo!
u can do it,do not give up
tum ye kar sakti ho('sakte ho' if talking to a male), haar mat maano

nahin chhoro means don't leave(or loose the grip) .

There are not exact words for these but we say it this way
if you want to encourage someone..
do not give up
means himmat na haaro

you can do it
tum yeh ker sukti ho

come on go for it
there is no exact word for it but most suitable is

haan yaar, aisa hi kero / tumhe aisa hi kerna chaiye
yes you can say shabash..but not shabashi

so" come on, go for it,... u can do it,..do not give up"
haan yaar, tumhe aisa hi kerna chaiye..tum yeh ker sukti ho, himmat na haaro