これはとても良い質問ですね。
何をしても家族が理解、サポートしてくれる。
実はサポートをそのまま使います。
My parents are supportive
家族は協力的です。
もしくは自主性に任せてるなのでニュアンス的には以下も使えると思います。
They trust me 信頼してくれている
They respect my decisions 尊敬している
Whatever you are trying to do, good luck!
You can also say 'have my back'.
For example: I know my family always has my back.
'Have my back' is a more casual expression to use for supportive. It means they are watching your back. It is more common to use this when talking about friends.
Have my back' も使えます。
例えば：
I know my family always has my back.（家族はいつも私を支えてくれます）
'Have my back' は 'Supportive'（支える）のカジュアルな言い方です。「背中を見守っている」という意味です。友達について言う場合にはこの表現の方が一般的です。
I'm thankful that my parents were always supportive.
When you say that they were "supportive" this means that they helped you. You may also say that your are "grateful"instead of "thankful" as they both have the same meanings. This implies that you are happy and are showing your gratitude for the way they treated you.
my parents were always supportive' は「両親はいつも応援してくれた」という意味です。
また、"thankful" の代わりに "grateful" も使えます。どちらも同じ意味です。これは、両親がそのように接してくれたことについて感謝していることを表します。
My parents have always been very supportive of me.
The verb form "have been" explains that in the past your parents were supportive of you and in the present, they are still supportive of you. You can add the word "always" for more emphasis. I hope that this helps. :)
Expressing this thought in the present tense conveys the idea that their support is ongoing. Using an adverb like "always" or "very" is also an effective way of emphasizing that they support you a lot or at all times. Parent's are their children's most important educators. And a "supportive" person is one who assists or helps others. The best parents are always supportive of their children.
My parents always back me to the hilt. They're amazing!
If you wish to explain that your parents are always supportive of you, you could apply the phrasal verb 'to back (someone) to the hilt', meaning 'to the maximum amount.'
両親がいつも応援してくれると伝えたいなら、句動詞の 'to back (someone) to the hilt'（最大限応援する）が使えます。'to the hilt' は「最大限」という意味です。
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