Try erase()
str = 'with all this stuff going down at the moment ';
words_to_remove = {'with ','all ','this ','at ','the '};
new_str = erase(str, words_to_remove)
Or if you have several words to remove, making it difficult to make a words_to_remove cell array manually
str = 'with all this stuff going down at the moment ';
words_to_remove = 'with,all,this,at,the';
words_to_remove = cellfun(@(x) {[x ' ']}, strsplit(words_to_remove, ','));
new_str = erase(str, words_to_remove)
