I have some queries related to grammar and punctuation which have been bothering me for quite some time. Most of them are to do with subject-verb agreement, which I tend to find confusing. I’ve used some examples from work/letters and some which I have made up on the spot. Any help would be really appreciated! #1 Firstly, compound subjects are so confusing to me! I understand that subjects such as bacon and eggs, Marks and Spencer (the shop) etc. count as compound subjects and both are singular and have singular verbs, but what about sentences such as these? Your ethos and emphasis on learning truly reflect/reflects my own thoughts on the matter and is/are something I look for in any good educational institution. The life experience and knowledge that I have gathered via other means is/are the ideal foundation for further education. With these two sentences, I originally thought a singular verb was appropriate (is), but having looked at them more closely, it seems like both the sentences work in the same way that "Mary and John are good friends" would work. The subjects are connected by and, yet they don't stand alone as a singular subject in the way that bacon and eggs do. Therefore they both require a plural verb (are), am I correct? I highlighted reflect/reflects because I'm not sure which is approrpiate and why. #2 Since people and experiences are the greatest source of knowledge there is… Again, I'm thinking that the subject people and experiences requires the plural. But when we come to greatest source of knowledge, that is singular (and so is the verb I've given it.) However, I want to know if it's OK to have both a singular and plural subject and a singular and plural verb in the same sentence. I suspect it is, but I just wanted to check. #3 Emphasis on community and student support is something that I, as a student, would/will find invaluable. Again, here I chose "would" - becomes I'm expressing something which I hope will happen in the future. Is this right? #4 Your ethos which states that “every individual has a unique and valuable contribution to make” is something that stood/stands out to me. Again, this one has left me confused. I'm not sure which one is correct or why. Both sound OK to me. #5 I left (somewhere) realising or I left having realised? #6 Is it OK to switch tenses as long as you don't do it within the same sentence? Thus: For the majority of last year she was unable to comitt to a study course due to the nature of her illness (past.) Then: She continues to be under investigation (present.) #7 Is the following sentence valid: My interests include theatre, arts and culture. It doesn't contain a verb, so I assume it is incorrect? #8 If you're using commas as an aside, is it ok to separate the subject from its verb. The film, with its spectacular effects and rich colours, was brilliant. # 9 - Final question! If you've listed an number of things and then begin the next sentence with, "All of which," should it be "all of which has served me" or "all of which have served me"? Any answers would be very much appreciated.