You use the Present Perfect or Present Perfect Continuous for actions that started in the past that have not stopped, E.g. I have been riding my bike (and I am still doing it now). For such a statement we use the PPC tense VERSUS If an action started and finished in the past, we use the Simple Past Tense. E.g. I rode my bike (an hour ago). I hope this helps

Visit southern cities in Iran. Fascinating beach!

A more formal way to write this: Is this job for experienced candidates or novices?

Everything's good, except for some punctuation errors, but I'm guessing this will be sent as a text so it's not really important.

1 - 'The product reaches our tables with the name of table salt' is the better of the two. 2 - 'Managers want their workers to take time away from work for their health and their own business' is more correct. I have to add that neither of the sentences sound natural. Rather use these: 1 - The product, named table salt, reaches our tables. 2 - Managers want their workers to take time away from work for the sake of their worker's health and to give them a chance to take care of their own obligations.

'Tell/told' is used to give someone information, e.g. I won’t tell anyone your secret. 'Say/said' is used when we quote people directly and also when we give instructions. We also use it for opinions and thoughts, e.g. Emma says she doesn’t like chocolate. So, 'Jessica said goodbye to me' is correct because Jessica is being quoted.

Think of a funnel divided into 3 parts. 'In' is at the top; it's is not specific, it is used to talk about time in general, for e.g. in the 90s, in 3 weeks, in Paris. (SO: years, months, weeks, countries, cities and neighborhoods.) 'On' is in the middle, it is more specific than 'in', for e.g. on the weekend, on July 12th, on Violet street. (SO: days, weekend, streets, lanes etc.) 'At' is at the bottom, it is very specific, for e.g. at 9 a.m., at 32 Herring Avenue (SO: hours, specific address or place). I hope this helps. If you have any more questions about prepositions or Grammar in general, you are welcome to book a lesson!

The Present Perfect is used to show a connection between the present and the past. The time of the action is not mentioned, and the outcome of the action is more important than the action itself. So..the action started in the past and continues in the present. E.g.: I have been to this place before. The Present Continuous tense is used for actions happening now or for an action that is unfinished. E.g. I am writing you a letter (I'm not finished and I'm doing it now). *the infinite tense is known as the Continuous tense