We are happy to hold the second largest meeting Second biggest meeting [not really any differences] Is supposed to ~ has been scheduled for ~ [suppose is like assume. the speaker is guessing that something will occur. Is scheduled - the speaker knows that the even has been planned for a specific time] I am pleased that Marathon begins~ Marathon starts~ [no real difference in this context] Tentative schedule Temporary schedule [tentative - something has been scheduled, but the schedule may change. it is not possible to schedule the event completely until closer to the date. Temporary schedule - this schedule has been designed to last for a while. Perhaps a classroom is undergoing repairs, and a temporary schedule is created for the duration] Keep in mind Take notes [keep in mind - make this knowledge important in your mind, please try to remember. sometimes this knowledge will be important to what i will say next. i.e. Keep in mind that the weather forecast is for rain tomorrow. What should we wear on our excursion? Take notes - write this down, it is detailed and you will need to reference this detail later. Not to be confused with: Take Note: notice this fact (like keep in mind, but more of a command than a suggestion)]