この薬は、正しく用いれば、たいへんききめがあるでしょう。

This medicine, properly used, will do you a lot of good.

この薬(くすり)は、正(まさ)しく用(もち)いれば、たいへんききめがあるでしょう。

Kono kusuri wa, masashiku mochiireba, taihen kikime ga aru deshō.

此の (この)

this (something or someone close to the speaker (including the speaker), or ideas expressed by the speaker)

薬 (くすり)

medicine; pharmaceuticals; (legal) drugs; efficacious chemical (i.e. gunpowder, pesticide, etc.); (pottery) glaze; small bribe

は (は)

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

正しく (まさしく)

surely; no doubt; evidently

用いる (もちいる)

to use; to make use of; to utilize; to utilise

大変 (たいへん)

very; greatly; immense; enormous; great; serious; grave; dreadful; terrible; difficult; hard; major incident; disaster

が (が)

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

有る (ある)

to be (usu. of inanimate objects); to exist; to live; to have; to be located; to be equipped with; to happen; to come about

デス (デス)

death

Readings: ヤク、くすり

Meanings: medicine, chemical, enamel, gunpowder, benefit

Readings: セイ、ショウ、ただ.しい、ただ.す、まさ、まさ.に

Meanings: correct, justice, righteous, 10**40

Readings: ヨウ、もち.いる

Meanings: utilize, business, service, use, employ