"My mom booked a table."

Translation: 我的妈妈订位了。

[edominey]

My Chinese teacher told me that 的 is not necessary for close relationships, so 我媽媽 should be acceptable.

[_Sorra_]

Em we can say 我的妈妈 and also we can say 我妈妈 , why it is wrong?

[Gabrielle145359]

Both should be correct, but without the 的 is more natural, I believe. They are both accepted now.

[versain67]

they don't

[geoffrey-liu]

Is it not possible to change the order of words a bit...

我妈妈订了位？

[mailto.mxi]

Should be acceptable.

In the different Chinese languanges you see subjects in different places of the sentence construction that are equally acceptable. This is one example.

[Rumactree]

I was wondering if that would work too.

[butisitbeautiful]

And table is not translated whatsoever?

[Martinolog]

it translates more to "booke a place" I guess...

[Noel435839]

You don't need to use 的 for or with family members.

[debrouillard]

As a native speaker my first thought was 我妈订了张桌子...

[FlviaGiese]

The verb "to book" doesn't have an object in this case?

[Keith_APP]

订 in itself means to book
位 means a seat / seats
Many words in Chinese are formed in this way including a verb and a noun at the same time for elaboration. Often this kind of words can be used both as a verb and as a noun (a similar application as a gerund).
e.g. 骑马 Ride + Horse

However, it would be a little bit tricky to add adverbs and adjectives to such phrases and stay natural. Please acknowledge it first and move on.

[Brillenschnecke]

订位 is selfexplaining and includes an object in this case as you only can use it when you reserve a table or a seat.

[Brillenschnecke]

订位 is selfexplaining in this case and includes the object here as you can only use this verb when you book a seat or reserve a table.

[MilanLin]

I had the correct solution: 我的妈妈订位了
It was marked wrong!

[JoyFuFu]

我的妈妈订了一个位子 should be accepted