It is common practice that at the end of an aliyah, people sing the last couple of words with the Ba’al Koreh. If these last words include Hashem’s name (e.g. Beresheet 6:8), is it permitted to sing along with the Ba’al Koreh, or would one be in violation of Lo Tisa?
It depends on what and how many words are bring said. If what is being said is a statement that can make sense on it’s own, even if ti isn’t a full posuk, it is permitted and not considered saying H-shem’s name in vain. However if the words are not something that can make sense on it’s own then it is not permitted.