Breakdown of watasi ha haha ni denwa wo simasu.
はha
topic particle
私watasi
I
をwo
direct object particle
母haha
mother
にni
indirect object particle
電話denwa
call
電話 を するdenwa wo suru
to call
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Questions & Answers about watasi ha haha ni denwa wo simasu.
What is the function of は in this sentence?
は is the topic marker. It tells us that we are talking about “I” (私). It sets 私 as the theme of the sentence.
Why is に used after 母 instead of を?
In Japanese, the person you call is marked with に (indirect object), while を marks the thing you’re acting upon (here, 電話, the call itself). So you call “to your mother” (母に), and you do a phone call (電話を).
What does 電話をします literally mean, and how does it translate naturally?
Literally it means “do a telephone call.” Naturally, it translates as “make a phone call.”
Can I use 電話をかけます instead of 電話をします? Are there any differences?
Yes, you can say 電話をかけます, which literally means “to hang (dial) a phone call.” Both expressions mean “to call someone,” and in daily conversation they are interchangeable. かける just emphasizes the act of dialing or connecting, while する is more general.
Why is the verb します instead of the dictionary form する?
します is the polite present form of する. In casual speech you might say 電話をする, but in polite/formal situations you use 電話をします.
Is it necessary to include 私は? Can I drop it?
You can often omit 私は because Japanese drops topics when they’re clear from context. 母に電話をします is perfectly natural if it’s obvious you’re talking about yourself.
Why does the verb come at the end of the sentence?
Japanese follows SOV (subject-object-verb) word order. Particles mark each element’s role, so the verb always appears at the end.