Group 1 - The article discusses the requirements for issuing VAT invoices, emphasizing that businesses must provide their taxpayer identification number or unified social credit code when requesting a VAT invoice [2] - It clarifies that invoices not filled out according to regulations cannot be used as tax certificates, and electronic invoices cannot be voided after issuance [2][3] - The article outlines the timing of VAT tax obligations, stating that tax obligations arise on the day of receiving payment or issuing an invoice for sales of goods or taxable services [3] Group 2 - It specifies that certain input tax amounts cannot be deducted from output tax, including those related to personal consumption and non-normal losses [3] - The article highlights that businesses must report taxes regardless of whether an invoice is issued, as long as taxable activities occur [3] - It mentions that specific scenarios do not require tax declaration, but warns against confusion regarding zero declarations [8]