Hello.<br/><br/>a) Is there a tin-opener/Are there any tin-openers in the house?<br/><br/>What is the difference or little difference in meaning?<br/><br/>b) We had to walk home because there was no bus /there were no buses /there weren't any buses / there wasn't a bus.<br/><br/>What is the difference or little difference in meaning?<br/><br/>Thanks.