how to save two variables csv file

how to save two variables csv file in matlab for x and t from wav file ,and do that for multiple wav file

I use this code to read the wav file

% load an audio file [x, fs] = audioread('a66.wav');

x = x(:, 1); % get the first channel N = length(x); % signal length t = (0:N-1)/fs; % time vector

save a66.csv x -ascii -double