To form the prepositional of plural nouns
Add -ах to masculine nouns ending in a hard consonant (мост → мостах).
Replace the -o of neuter nouns ending in -o with -ах (окно → окнах).
For masculine nouns ending in -й, -ь and neuter nouns ending in -е, replace these endings with -ях (учитель → учителях, море → морях).
For feminine nouns ending in -a, add -х (рука → руках).
For feminine nouns ending in -я, add -х (неделя (week) → неделях).
That's a somewhat misleading rule. It's more accurate to say that the new information goes at the end of the sentence. "Кошка у меня в руках" tells us where the cat is. It's in my arms. "У меня в руках кошка" tells us what's in my arms - a cat. Here's a good post about word order: https://forum.duolingo.com/comment/13955228
Not sure how idiomatic this translation is though.
The thing is: Russian "У меня в руках" means that you are actively gripping something. If you release your grip, that thing or creature will fall or escape. On the other hand, if you merely supporting something/someone using your hands, you'll say "У меня на руках". So, if you are lounging on your sofa while leisurely holding a cat, "У меня на руках кошка" would be a better translation.
For the same reason, it's "У неё на руках ребенок"="she is holding a baby" if she is cradling the baby in her arms.
Fascinating, had no idea. Still trying to grasp the distinction though. If you're going for a walk holding your cat, would it be "в руках"? Is the baby case a sort of an exception to the "if you release your grip" condition? I normally think the baby would fall if you were to stop holding them and you're standing up.
I guess the distinction is not so much the possibility of a fall as the nature of the grip itself: it's gripping something with your hands (e.g., a bag) vs. providing support (as in the case of a baby). So if you've caught a cat and are holding it firmly in your grip → в руках; if you are cradling a cat → на руках.
Also, remember that Russian does not commonly make a distinction between hands and arms (it can, but it normally does not), hence "на руках" need not refer to one's palms.
Interesting. Hadn't realized this was also an idiom, but it sure looks like it is: http://context.reverso.net/translation/english-russian/i%27m+holding# Thanks for mentioning it.
To me in American English at least, there's nothing strange at all about "I've got a cat in my arms" (some of the other things being "held" in the Reverso database would have made it more obvious :) Out of curiosity, it's weird in British English?
Держать руками? Yes, it is possible, but it is not a usual thing to say (same as "hold with hands" in English). Here are some corpus examples:
- Руку друга детства Юлька держала двумя руками. ~ Yulia held her childhood friend's hand with her both hands.
- Володя обеими руками держал бамбук спиннинга ...
- Наган был такой тяжелый, что ей пришлось стрелять, держа его двумя руками.