Double blind placebo controlled trial - 89 фото и картинок
Double blind placebo controlled trial.
Randomized, Double-Blind, Placebo-Controlled Trial.
Randomized Clinical Trial.
Double Blind Trial.
Randomized Placebo-Controlled.
Randomized Blind Placebo-Controlled.
Past simple present Continuous present perfect.
Perfect Tenses в английском языке таблица.