"Last week, I called my friend in Japan over the phone."

Translation: 先週、日本の友だちに電話をかけました。

[deepfriedmcrib]

This is a bit misleading as there is a difference between a "Japanese friend," which the Duolingo appears to want, and a "friend in Japan."

[sketchdesk]

These particles (ni, wo, etc.) Are confusing

[Peepo10]

They can be!
But there are some easy to follow rules for most of them, where は is usually a subject indicator
に usually indicates a place whether it be about the place, a verb involving a place (theres also へ but its slightly different as its only for going towards the general area)
を is always paired with a verb; so an action of sorts!
で is often used to indicate by what means did they do something, like
"箸(はし)で寿司(すし)を食(た)べました"
Which means "With these chopsticks, I ate sushi"

[VeranoJoe]

Is using "denwa de" incorrect in this exercise? Because i can say i called my friend "by means of" the phone

[DDNeuro]

i used 友達 and it said i was wrong?

[Moosey007]

先週日本にいる友達に電話しました

[SomerSeitz]

They made this confusing, in Japan would have the particle ni?

[ninjaojiisan]

some how I'm missing shi in the word bank

[Heioqei]

Same for me.

[GunnarSchaan]

The single 'shi' syllable is missing.

[Motowasi]

I think its "nihon no Tomodachi" for "friend in Japan" and it would be "nihon jin no Tomodachi" for "japanese friend"

[RobbPorter]

Why isn't it Nihon NI Tomodachi? Wouldn't you use NO if you were going to say "Japanese friend" rather than "friend in Japan"?