I don't understand this sentence もう声が出ず体でうなずいて

Question

I'm reading a story about a taxi driver picking up a young girl. He is driving when he notices that the girl has disappeared. However, at a certain point he hears her voice telling him to change his destination. At this point I found this sentence: もう声が出ず体でうなずいて真っ直ぐ前だけ見て走らせた。 What does the part in bold mean?

Answer 1

Lets break this down, and see what we can get out of this sentence.

声が出ず: You're going to find a really good grammar here ～ず。 If you want to do some research, look here. Simply put, it is a grammar where you do something without doing something else. This portion translates to without using his voice

Here's another example of ～ず usage:

忘れずにやりました。(I did it without forgetting)

もう: This is probably one of the most important parts of the sentence. As you'll see discussed in the comments below, もう changes the meaning of 声が出ず from without using his/her voice to unable to use his/her voice.

体{からだ}で：　Literally translates as "with the body."

うなずいて: This is a conjugation of うなずく、whose translation can be found here. However, you'll also find that うなずいて also has a definition listed on jisho.org. Compounded with 体で we get: Nodding with his/her body.

Ok, now lets put it all together:

もう声が出ず体でうなずいて真っ直ぐ前だけ見て走らせた。

Unable to speak, he/she nodded with his/her body, and ran straight forward not looking left or right.

I want to add an appendage that 前だけ見て means only looking forward. In translating that to English, I changed it to without looking left or right.

Hope it helps.

Answer 2

Literally, "His voice no longer came out and he nodded with his body [only]". Presumably he is so scared by hearing her voice after she has disappeared that he cannot speak, only nod. I'd suggest "His voice failed him. He could only nod silently. He drove on with his eyes fixed straight ahead".