英和和英

by main strength

to do all one can―do everything in one's power―do one's best―do my utmost

I will do all I can―do everything in my power―do my best.

Do your best [utmost].

make one's (best) endeavor(s)

doing one's best

Do your best.

Let's do our best!

Give it all you've got.

the state of all one's energies being spent

I will do my best.

Do your best!

I will exert myself to the best of my ability―exert myself to the utmost―do all I can―do all that lies in my power―do all that in me lies―do the utmost in my power―do my best.

do one's (level) best

Do your very best.

I put my all into everything.

try one's best

I will do all I can―do the best I can―do my best―do my utmost―do everything in my power―do all that in me lies―do all that lies in my power―use my best exertions―use my best endeavours―use my utmost endeavours.

I'll do my best.

to concentrate all one's powers on one object―bring all one's energies to bear upon one object

the action of confronting something with all one's energy

Fight with all your might.

try one's best [hardest]

do [try] one's utmost

to do something with all one's strength

Please do your very best.

Do your very best.

I will do my best when I am put to the push.

Do your best.

Do your best!