тяжёлого

difficult, hard, heavy

→ тяжёлый

тяжёл severe, serious + ого Genitive singular (also animate masculine accusative)

adjective · singular masculine, genitive / singular neuter, genitive / singular masculine, accusative Rare #41,006

difficult, hard This form is used with masculine or neuter nouns in the genitive or with masculine animate nouns in the accusative.

RU: После тяжёлого дня я рано лёг спать.

EN: After a hard day, I went to bed early.

heavy This form is used with masculine or neuter nouns in the genitive or with masculine animate nouns in the accusative.

RU: В коробке нет ничего тяжёлого.

EN: There’s nothing heavy in the box.

Forms of тяжёлый

	Masculine	Feminine
Singular	тяжёлый	тяжелая

She is suffering from a serious illness.

I'm back home after a hard day!

— С меня хватит! (1993)

What's so heavy in these boxes?