Here is another common mistake I have heard from some of my Japanese students.
"Dave is very kindly."
Kindly ends with an いい (EE) sound *BUT* words that have an いい (EE) sound are NOT ALWAYS adjectives in English! (Remember this post? English adjectives 形容詞)
Kindly is an adverb (副詞). Many adverbs end with 'LY' so be careful, an adverb can ONLY be used to describe verbs (an action/動詞), not nouns (a person, place or thing/名詞)
Here are some common adverb examples:
carefully "Karen drives very carefully."
Drive is a verb so if we want to describe how do someone drives (or describe their driving) we can use the adverb carefully.
quickly "Usain Bolt runs quickly."
Run is a verb so we use the adverb quickly to describe it.
gently “Bob kisses his baby’s head gently.”
Kiss is also a verb...
The word 'Dave' is a noun from our first sentence, so we need an adjective to describe him (me!). The adjective is kind so we would say...
"Dave is very kind."
What a nice thing to say! Thank you very much!