"J'ai oublié ma casquette alors tu peux me prêter la tienne ?"

Translation: I forgot my cap, so can you lend me yours?

[GraemeSarg]

I put "could you lend me yours" without thinking about it, and to my amazement it was accepted! How very un-American!

[Billfrench]

actually, it is just as "american" as "can", just not in the duo world., though duo has actually used it in the past with all that should/shall, could/can/will stuff (is that true?) that annoyed soooo many people. that being said, strictly speaking would that be the correct conjugation?.

[FelixMango2]

Yes i can provided i inspect your hair for any sign of lice