このナイフは

this knife

→ 此の
phrase Rare #28,185
this knife この means “this,” ナイフ means “knife,” and は marks the topic. This phrase usually introduces a statement about the knife and is not normally used by itself as a complete sentence.
JA: このナイフは野菜を切るのに便利です。
EN: This knife is useful for cutting vegetables.

このナイフはあまり切れない

This knife isn't very sharp.

このナイフは肉を切るために使われる

This knife is used to cut meat.

このナイフは私にはとても便利でした

This knife was very useful to me.

このナイフはとてもよく切れる

This knife is very sharp.

このナイフは良く切れない

This knife doesn't cut very well.