ON Verizon cell phones, the green checkmark means the message has been delivered to the recipient's mobile device. When sending a txt (or pic or flic) messge to a non VZW customer, there will be a green arrow indicating that the message was sent, not neccaserily that they received it.
Witness marks.
These text symbols are called bullet points. They are often used to introduce items in a list to make the information easier to read and understand. Common symbols include small circles, check marks, dashes, or arrows.
On the IMO app, a single check mark next to your message indicates it has been sent, while two check marks mean it has been delivered to the recipient. If the two check marks turn blue, it signifies that the recipient has read your message. However, keep in mind that read receipts may be disabled by the user, so you might not always see this indication.
They are lines and arrows on the sprockets and engine.
The check marks represent apps you have downloaded and installed. To view them, touch the area on the phone where the check marks are and fling downward.
A clock icon on WhatsApp indicates that a message has been sent but not yet delivered to the recipient. This usually means that the recipient's phone is offline or they have not yet connected to the internet. Once the message is delivered, the clock will change to a single check mark, and when the recipient reads it, it will turn into two check marks.
I don't see three arrows down as any typical proofreading mark. Is it possible that what you are seeing as three down arrows is an indication to insert quotation marks? That's the closest idea that I can come up with. You may need to consult with your proofreader to clarify the symbol. (If someone's willing to read and make marks on your work, s/he will be happy to clarify those marks' meanings.)
check both of your pulleys,they have marks on them.
Tick marks are the check marks, x's or other marks made next to items on a list.
The timing belt marks on a 1994 Honda Civic are found on the cam shafts. The arrows will needed to be point a TDC in order to install the belt properly.
If it is a gs there are little marks on the engine the left camshaft is about 11:00 and the right is about 9:00 you will see the marks if you look close enough the crank is at 12:00 there is little arrows and yellow dots on the cam sprockets The marks on the engine are like little nipples
They don't mean anything, there just quotation marks.