Twins are cute but I've heard that they're hard work!
I think that twins are cute but I've heard that it's hard work raising them.
「双子」＝「twins」
「可愛い」＝「cute」
双子は可愛いけど
Twins are cute but...
「育てる」＝「bringing them up」や「raising them」、「looking after them」
「大変」＝「hard」、「difficult」、「hard work」
育てるのが大変と聞きました
I've heard that bringing them up is hard work
※「bringing them up」は主にイギリス英語です。アメリカ英語では「raising them」という言い方の方が使われているそうです。
私の意見では、こちらが最も自然な言い方です：
Twins are cute but I've heard that they're hard work!
I think twins would be cute but I am afraid they would be hard to raise.
I like the idea of twins but I am not sure I could raise them.
I heard it would be hard to raise twins even though I do think they are cute.
I think twins would be cute but I am afraid they would be hard to raise.
I like the idea of twins but I am not sure I could raise them.
I heard it would be hard to raise twins even though I do think they are cute.
I think I should raise just one child before I try two at once.
Twins look cute but they look like a lot of work.
I think twins would be cute but I am afraid they would be hard to raise.
（双子はかわいいけれど、育てるのが大変だと思います。）
I like the idea of twins but I am not sure I could raise them.
（双子はいいなと思うけれど、私に育てられるかわかりません。）
I heard it would be hard to raise twins even though I do think they are cute.
（双子は可愛いと思うけれど、育てるのが大変と聞きました。）
I think I should raise just one child before I try two at once.
（双子を産む前に、1人育ててみるべきだと思います。）
Twins look cute but they look like a lot of work.
（双子は可愛いけれど、大変そうです。）
"Twins are cute but hard work!"
The term 'Hard work' often used, this refers something that is not easy, it can be used in a context of things, ex. "Learning to drive is hard work" "playing football is hard work".
"Raising twins sounds great but a handful!"
A 'Handful' is another expression used to describe 'hard work', something that can be challenging.
"Twins are cute but hard work!"
（双子はかわいいけれど、大変だ！）
'Hard work'とは、あることが容易ではないことを意味します。
例： "Learning to drive is hard work"
（運転を習うのは大変だ。）
"playing football is hard work"
（フットボールをするのは大変だ。）
'Handful' とは、あることが大変であることを意味します。
Twins are sweet, but I heard that they are hard work.
Twins are cute but they are also double the trouble!
Someone asks if you want twins. You want to say that twins are cute, but had heard that they are hard to raise. Please see if one of the above suggestions is appropriate for your situation.
Twins are cute but I heard that they are hard to raise
I like the idea of having twins but I've heard that they are hard to raise
When you want to explain that you think twins are cute but you have heard that they are hard to raise; then you may express this in the following ways:
-Twins are cute but I heard that they are hard to raise
-I like the idea of having twins but I've heard that they are hard to raise
「双子はかわいいけど、育てるのが難しいと聞いた」は次のように言えます。
-Twins are cute but I heard that they are hard to raise（双子はかわいいけど、育てるのが難しいと聞きました）
-I like the idea of having twins but I've heard that they are hard to raise（双子の子を持つというのはいいですけど、双子は育てるのが難しいと聞いたことがあります）
Having twins might be cute, but it is expensive to take care of them.
I think twin babies are cute, but they are hard to raise.
"Having twins might be cute...."
For this answer it means that having two babies might "sound" fun or the babies may be cute together, but taking care of all of their needs will cost a lot of money.
"I think twin babies are cute..."
This is similar to the first answer, but a little different. Having two babies may be cute to see together or watch them learn together, but raising them will take a lot of time and a lot of money.
"Having twins might be cute...."
→ここでは「双子の子を持つのは楽しいだろうけど［双子は二人そろったらかわいいだろうけど］、育てるのにはすごくお金がかかる」と伝えています。
"I think twin babies are cute..."
→これは一つ目の例と似ていますが、少し違います。「双子が二人そろったら見ていてかわいいだろうけど、育てるのには時間とお金がかかる」と伝えています。
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